diff --git a/smop/graphviz.py b/smop/graphviz.py
index 25f90981..79a91456 100644
--- a/smop/graphviz.py
+++ b/smop/graphviz.py
@@ -7,12 +7,14 @@ def resolve(t,fp,func_name):
     fp.write('graph [rankdir="LR"];\n')
     for u in node.postorder(t):
         if u.__class__ in (node.ident,node.param):
-            fp.write("%s [label=%s_%s_%s];\n" % (u.lexpos,u.name,u.lineno,u.lexpos))
+            fp.write("%s [label=%s_%s_%s];\n" % (u.lexpos,u.name,u.lineno,u.column))
             if u.defs:
                 for v in u.defs:
                     fp.write("%s -> %s" % (u.lexpos,v.lexpos))
                     if u.lexpos < v.lexpos:
                         fp.write('[color=red]')
+                    else:
+                        fp.write('[label=%s.%s]' % (v.lineno,v.column))
                     fp.write(';\n')
     fp.write("}\n")
 
diff --git a/smop/node.py b/smop/node.py
index bcfed61d..2f55ce59 100644
--- a/smop/node.py
+++ b/smop/node.py
@@ -118,7 +118,7 @@ class number(atom,recordtype("number","value lineno lexpos",default=None)):
     def __str__(self):
         return str(self.value)
 
-class ident(atom,recordtype("ident","name lineno lexpos defs",default=None)):
+class ident(atom,recordtype("ident","name lineno column lexpos defs",default=None)):
     def __str__(self):
         return self.name
 
diff --git a/smop/parse.py b/smop/parse.py
index f45c255e..e98a6f36 100644
--- a/smop/parse.py
+++ b/smop/parse.py
@@ -489,9 +489,11 @@ def p_expr_ident(p):
     if p[1] == "nargin":
         global use_nargin
         use_nargin += 1
+    #import pdb; pdb.set_trace()
     p[0] = node.ident(name=p[1],
                       lineno=p.lineno(1),
-                      lexpos=p.lexpos(1))
+                      lexpos=p.lexpos(1),
+                      column=p.lexpos(1) - p.lexer.lexdata.rfind("\n",0,p.lexpos(1)))
 
 def p_expr_number(p):
     "number : NUMBER"